Bernard piffard



UNITED STATES PATENT OFFICE.

BERNARD PIFFARD, OF HEMEL HEMPSTEAD, ENGLAND.

MANUFACTURE OF VARNISH.

SPECIFICATION forming part of Letters Patent No. 441,853, dated December 2, 1890. Application filed July 31, 1890. Serial No. 360,561. (No specimens.)

To all whom it may concern:

Be it known that I, BERNARD PIFFARD, gentleman, a subject of the Queen of Great Britain, residing at Hill House, Redbourn Road, Hemel I-Iempstead, in the county of Herts, England, have invented certain new and useful Improvements in the Manufacture of Varnishes, of which the following is a specification.

This invention has for its object improvements in the manufacture of varnishes.

I produce in the first instance the lead salts of the isomeric acids constituting oolophony, and I add beeswax to the colophon y previous to the application of heat. This prevents the deterioration of the color of the colophony and improves the varnish made from the lead salts. I prefer to proceed as follows: I take rosin and mix it with the lead oxides (preferably litharge) in the proportion of two rosin and one lead oxide, and I add one-twelfth to one-sixth of beeswax. In place of beeswax I can employ other bodies of a waxy nature, as paraftlne. To this mixture I apply a heat of about 250 in an oven till combination is obtained,stirring frequently. When combination is complete, the heat should be kept up till the excess of oxide has subsided, and the supernatant liquid should then be passed off, allowed to cool,and ground to a fine powder. I then mix the powder with rectified benzole or rectified turpentine or other solvent in the proportion of two parts, by weight, of the lead salt to three parts, fluid measure, of the solvent. I then raise the mixture to boiling heat and keep it at that heat till the liquid becomes transparent, but no longer. The reason for continuing the heat till clear is that some one or other or others of the oolophonates are not so soluble as the other or others. They must all be dissolved togather. The varnish maybe used hot or cold, according, to circumstances, and hardens rapidly.

hat I claim isr l. A varnish consisting of oolophonate of 1ead,wax or waxy matter, and a solvent, combined substantially as described.

2. The herein-described process of manufacturinp varnishes,which consists in mixing colophony with lead oxide and wax or waxy matter, then fusing the mixture, then drawing off the clear liquid portion, and afterward dissolving it in a solvent.

BERNARD PIFFARD.

Witnesses:

GEO. W. FRANKLIN, JOSEPH LAKE, Both of 17 Gracechurch Street, L0nd0n,E. O. 

